Roll up roman shade

Abstract

An improved expandable and contractible window covering comprising a series of elongated cells is disclosed. Each cell is formed by joining a pleated sheet of material with an unpleated sheet in an area of creases on the pleated sheet. The rear wall of the cell is of less height than the front wall of the cell and the material of the cell is chosen to be relatively soft and flexible so that the front wall of each cell droops downwardly and outwardly away from the rear wall. The covering is mountable on a roll bar so as to be retracted by rolling about the roll bar and extended by unrolling from the roll bar.

What is claimed is: 
     
       1. A cellular shade for covering an architectural opening comprising in combination a first sheet of planar, unpleated, flexible material having a width and a length, said first sheet defining a set of joint lines extending across the width thereof and spaced apart along the length thereof, a second sheet of flexible material having a width and a length, the width of said second sheet being substantially equal to the width of said first sheet, and the length of said second sheet being longer than the length of said first sheet, said second sheet having a set of joint lines extending across the width thereof and spaced apart along the length thereof, the spacing between said joint lines on said second sheet being substantially greater than the spacing between said joint lines on said first sheet, a connector fixedly joining said first sheet at said joint lines thereon to said second sheet at corresponding joint lines thereon to form a plurality of parallel cells extending across the width of said sheet, said first sheet defining a planar, unpleated rear wall of each of said cells and said second sheet defining the front wall of each of said cells, which said front wall forms a curved drooping surface projecting outwardly and away from the back wall of each cell, a roll bar about which the connected first and second sheets can be wrapped, and a connection system for operatively connecting the first and second sheets to said roll bar. 
     
     
       2. A cellular shade as defined in claim 1 wherein said joint lines on said second sheet of flexible material are creases. 
     
     
       3. A cellular shade as defined in claim 2 wherein said curved drooping surface has a lowermost edge and said lowermost edge is at least as low as the lowermost joint line corresponding to the associated cell. 
     
     
       4. The shade of claim 1 wherein said connection system includes elongated strip of somewhat rigid material secured to one of said sheets and a recess on said roll bar adapted to releasably retain said strip. 
     
     
       5. A cellular shade of claim 4 wherein said strip is connected to said first sheet.